Fig. 2

Deletion of Brca1 in p18^−/− or p16^−/− epithelia activates Pdgfrβ-Pkcα signaling and EMT in basal-like tumors. a–c Representative immunostaining of tumors from p18^−/−, p18^−/−;Brca1^MGKO, and p16^−/−;Brca1^MGKO mice. Pdgfrβ⁺ tumor cells (Ck14⁺ Pdgfrβ⁺, white arrows) and stromal cells (Pdgfrβ⁺, red arrow) are indicated. Note the widely spread Pdgfrβ and Ck14 doubly positive cells in a p16^−/−;Brca1^MGKO primary mammary tumor and its lung metastasis (b). d Tumors (T) from two independent p18^−/−;Brca1^MGKO mice (mouse 1, 10 months old; and mouse 2, 18 months old) were analyzed by western blot. Tumor-free mammary glands (MG) from the same mouse were used as controls. e Tumor cells from three independent mice were cultured and analyzed. Protein bands were quantified by Image-Pro Plus 6.0